use Date::Calc qw(Add_Delta_Days);
use Time::Local;

my $date = '31.01.2005';
my ($day,$month,$year) = split(/\./,$date);
($day,$month,$year) = Add_Delta_Days($day,$month,$year,1);

my $timestamp = timelocal(0,0,0,$day,$month-1,$year-1900);